I've been resisting using this one because it lends itself to overanalysis and I am not interested in doing that. So I'll just make two comments:
1. Ernie really needs to learn that not everything in the world is about him. But according to Piaget (I think), preschoolers tend to go through a developmental phase of extreme self-centeredness. In other words, there seems to be a pedagogical method to the madness.
2. Ernie hums a few bars of the Northwestern University fight song, which--in my opinion--is really random.